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    <title>Document</title>
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    <script>
      function has(arr, num) {
        if (arr.indexOf(num) == -1) return false;
        else return true;
      }
      var arr = [1, 2, 3, 60];
      var arr_1 = [1, 2, 3];
      var arr_2 = [1, 2, 3, 30, 25, 61];
      console.log(has(arr, 60));
      console.log(has(arr_1, 60));
      console.log(has(arr_2, 30));
    </script>
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